JBL Tune Flex earbuds won't pair with more than one Apple device

I have a pair of JBL TUNE FLEX Earbuds. I cannot get them to pair to my iPhone, iPad, and MacBook Pro. If I want to use them with a different devise I have to tell the devise they are paired with, even with it says Not Connected, to Forget Devise before the Earbuds will even appear on the other Devises's Bluetooth list for me to select and pair together. Any suggestions?

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